Just three years ago, petroleum engineering wasn’t an especially hot major for college students looking to enter a field with plentiful jobs. A recent study of 60,000 college students, including 2,400 in Texas, by Universum, a Stockholm-based company, found that students view jobs at oil and gas companies as much more desirable than even a year ago. Top salaries paid by energy companies are making energy jobs a hot ticket on college campuses.